Can someone recover from a cortical venous thrombosis without any residual neurological deficit?

Yes but not a given: Early diagnosis and treatment of cvt involves anticoagulants like heparin, and in the earliest diagnosed cases, intravenous recombinant tissue-type plasminogen activator (rt-pa) must be administered within 3 hours of symptom onset. Doing this can dissolve the clot and allow full return of venous flow with no residual effects, provided the patient is not at too great a risk for massive hemorrhage.